title: Cysteine 195 has a critical functional role in catalysis by isocitrate lyase from Escherichia coli.
abstract: Cysteine 195 in isocitrate lyase from Escherichia coli has been replaced by directed mutagenesis. Substitution by Ser yields enzyme with a k(cat) that is 0.03% that of wild type, and substitution by Ala, Gly, Thr, or Val yields completely inactive enzyme. The present results are consistent with a functional role of Cys 195.
authors.affiliation: Department of Biochemistry and Biophysics, Washington State University, Pullman 99164-4660, USA.
authors.forename: A
authors.initials: A
authors.lastname: Rehman
authors.forename: B A
authors.initials: BA
authors.lastname: McFadden
mesh_terms: D000409:Alanine / Q000235:genetics; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D003545:Cysteine / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics*; D005998:Glycine / Q000235:genetics; D007522:Isocitrate Lyase / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010957:Plasmids; D016415:Sequence Alignment; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D012694:Serine / Q000235:genetics; D013912:Threonine / Q000235:genetics; D014633:Valine / Q000235:genetics
chemical_list: D013912:Threonine; D012694:Serine; D007522:Isocitrate Lyase; D014633:Valine; D003545:Cysteine; D000409:Alanine; D005998:Glycine